1	Study of Radiation and Non-radiation Factors Influence on Development of Malignant Tumors for Nuclear Workers of the Mayak PA Z.B Tokarskaya, G.V. Zhuntova Southern Ural Biophysics Institute, Ozyorsk
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5	"Multivariate analysis is rather difficult..." Multivariate analysis is rather difficult to perform for large cohort studies since it is practically impossible to obtain a comprehensive and valid information on prevalence of some risk factors, particularly, social ones. The case-control studies require smaller contingents, which makes possible to obtain a comprehensive, accurate primary information.
6	Lung Cancer Study of lung cancer incidence for the Mayak workers was of primary interest because the lung is an organ of ²³⁹Pu deposition after inhalation. In addition, it is the most common malignant tumor site especially for males.
7	We studied the influence of the following factors on lung cancer: ²³⁹Pu body burden total external g -exposure chemical agents (prior exposure) smoking chronic lung obstructive disease Multivariate unconditional logistic regression was used to estimate odds ratio (OR). Attributable risk (AR) of the studied factors was also estimated.
8	Lung Cancer
9	Association between different histological types of lung cancer and risk factors
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11	Results of these studies were published in Health Physics: Z.B. Tokarskaya, N.D. Okladnikova, Z.D. Belyaeva, E.G. Drozhko The influence of radiation and non-radiation factors on the lung cancer incidence among workers of the Mayak nuclear enterprise (69: 356-366; 1995). Multifactorial analysis of lung cancer dose-response relationships for workers at the Mayak nuclear enterprise (73: 899-905; 1997).
12	"This study was continued in..." This study was continued in the framework of collaboration with LRRI with active participation of Dr. B. Scott We have used a multivariate analysis approach to investigate the pair-wise interactions of the three main etiological factors for lung cancer induction : ²³⁹Pu body burden, external g-radiation, smoking
13	Criteria used for evaluating interactions are as follows: Additive effect of factors A and B ORAB= ORA + ORB – 1 Multiplicative effect of factors A and B ORAB= ORA * ORB Confidence intervals for the expected ORAB under the additive and multiplicative models were generated via Monte Carlo calculations.
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16	"Obtained results confirm current concepts..." Obtained results confirm current concepts that carcinogenesis is a multiphase, polyetiological process. Information on the interaction between radiation and non-radiation factors is important for a more accurate estimation of radiation risks, dose dependence and threshold.
17	This study was published in Health Physics: Z.B. Tokarskaya, B.R. Scott, G.V. Zhuntova, N.D. Okladnikova, Z.D. Belyaeva, V.F. Khokhryakov, H. Schollnberger, E.K. Vasilenko Interaction of radiation and smoking in lung cancer induction among workers at the Mayak nuclear enterprise, Vol. 83, No 6, p. 833-847
18	Liver and biliary tract cancer Liver is one of the main organs of Pu deposition. In the framework of joint Project with Dr. B. Scott, we carry out research on the comparative contribution of radiation and non-radiation factors in development of malignant tumors in liver and biliary ducts using the case-control method.
19	Liver and biliary tract cancer
20	Association between liver and biliary tract malignancies and different risk factors
21	Radiation and non-radiation risk regions for development of malignancies among Mayak workers
22	Distribution of liver tumors for Mayak workers and ²³²Th-associated liver malignancies
23	Histological types of a-induced liver tumors and tumors in unexposed populations
24	Comparison of ²³⁹Pu and ²³²Th-induced liver tumors
25	Conclusion The major contribution in morbidity due to lung and liver cancers was made by non-radiation factors, especially smoking (for lung cancer), alcohol and viral hepatitis (for liver cancer). Influence of radiation factors on development of these tumors was found only at very high exposure levels multiply exceeding the permissible levels.
26	Conclusion (continue) Interaction of radiation factors and smoking (additive and multiplicative effect) was revealed for the lung cancer, which is important to take into account for a more accurate estimation of the dose dependence and threshold.
27	Continued study will be focused on the following: adjustment of the dose dependence and threshold estimates for lung cancer and malignant liver tumors; study the interaction between radiation and non-radiation factors for liver tumors;
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